This invention relates in general to cooking ranges and in particular to powered gas-fired cooking ranges.
The range of the present invention is of the high performance type finding its major applications in commercial and institutional cooking. Although the advantages of fuel-saving and reduction of pollutants are also of interest and value in residential cooking equipment, the potential for reduced fuel costs and high efficiency is most attractive in volume cooking operations.
Commercial ranges of the gas-fired type currently in use do not differ significantly from domestic ranges except for their greater size and capacity and more durable construction. Generally, gas is introduced at relatively low standard pressure to be mixed with combustion air at atmospheric pressure. Turndown for each burner is individually controlled after ignition from a constantly burning pilot which serves all burners. Another characteristic which commercial ranges have in common with domestic ranges is very poor efficiency of heat transfer from burner to cooking utensil.
Some efforts have been made to improve efficiency of heat transfer by pressurizing input combustion air, but generally the piping and equipment for such arrangements has been undesirably expensive and awkward to incorporate in a range of acceptable size. Moreover, maintaining desired fuel/air relationships has proven difficult, especially as burners are typically operated over wide ranges of turn-down, in some cases from 1/5 to 1/10 of rated input.
It has also been attempted to design burners in configurations which direct more of the available output heat to the cooking utensil. However, only minimal progress has been made in this direction.
It is, therefore, an object of the present invention to increase efficiency in gas-fired cooking ranges, especially of the commercial and institutional type.
Another object of the invention is to simplify and make practical the use of powered combustion in cooking ranges.
Still another object of the invention is the modification of the design of cooking range burners to improve the transfer of heat to cooking utensils.
A further object of the invention is the provision of an economical and dependable burner ignition and control system.